Hertel 84579879 Jobber Drill 31/64 Inch Tin Hss 135 Degree

Product Description

The HERTEL 84579879 is a jobber-length drill bit engineered for heavy-duty holemaking in metal and general-purpose shop applications. Ground from high speed steel (HSS) with a titanium nitride (TiN) coating, it delivers extended tool life and reduced friction across repeated drilling cycles. The 135-degree split point self-centers on contact, minimizing walking without a center punch. At 5.875 inches overall length with a 4.375-inch flute, this is a standard jobber geometry suited to drill presses, CNC machining centers, and hand-held power drills used by machinists, maintenance techs, and fabricators.

This drill bit is sized at 31/64 inch (0.4844 inch decimal), placing it in the 0.4000 to 0.5000 inch diameter range. It is well suited to production holemaking, general fabrication, and maintenance operations where a reliable, consistent hole diameter in steel, cast iron, aluminum, and similar materials is required. The straight-cylindrical shank seats cleanly in standard drill chucks and collets without requiring a specialized holder.

Key Features

• TiN coating increases surface hardness and reduces built-up edge for longer service life
• 135-degree split point self-centers and reduces thrust force at entry
• Web-thinned tapered web lowers cutting resistance and improves chip evacuation
• Two-flute regular spiral geometry clears chips efficiently in through-hole and blind-hole drilling
• Heavy-duty grade HSS construction withstands demanding drilling cycles
• NAS specification designation confirms dimensional and material compliance to an industry standard

Compatibility

Designed as an OEM-style jobber drill for use in any standard drill chuck or collet accepting a 31/64-inch straight-cylindrical shank across drill presses, hand drills, and CNC drilling equipment.

Installation Notes

Secure the shank fully in the chuck or collet before beginning any drilling operation and verify the workpiece is clamped or fixtured. Disconnect or de-energize the machine before changing bits. Use appropriate cutting fluid or coolant for the workpiece material to maximize tool life; note that this drill does not support coolant-through delivery. Inspect the cutting edges for chipping or wear before each use and replace when point geometry degrades to avoid oversize holes or workpiece damage.